I would say something along the lines of, "Here's to you and your new licence!".

By the way, notice, "licence" not "license". The spelling with a 'c' is the UK spelling and the 's' is American.
To confuse the issue even further, "license" is a verb in the UK. "He gave him license to celebrate Christmas" or "He gave him a licence to celebrate Christmas". It's a dreadful language to learn sometimes.